It's not the bite, so what is it?

So I started playing The Walking Dead Game Season 1 to fill myself up for waiting for season 2, and do you guys remember when Ben told the group that it's "NOT THE BITE THAT DOES IT"? Well, I'm just wondering if it's not the bite that does it, how come Lee died because of the bite?

You've got to wonder how any of these characters are still alive. I mean, isn't there a chance of getting their blood in you when one is killed close to you? What about when you've got an open wound and kill one point-blank? Or if one falls into a water source? These guys are also constantly running around with all this blood on them and on their hands.

It seems like Robert Kirkman's model (which the game and tv show adapt) for the zombie closely resembles the Max Brooks model. In the Brooks model, the reason there are zombies is because of a unknown and incurable virus he calls Solanum if i remember right. Solanum is transferable in much the same way that someone might get HIV/AIDS, and in his world, the zombie's main motivation is to transfer this virus. So when they bite or scratch you to point of blood being drawn, then you will turn into a zombie.

Kirkmans zombie model differs in that it seems instead of a virus, zombification in his world is the result of some kind of pathogen or fungus. So the zombie doesn't pass a zombie virus to directly you in his world, because you're already infected with the zombie virus. What im guessing happens is if you get bitten by a zombie, you die in much the same way that a Komodo Dragon kills its prey - which is a very very dirty mouth.. LOL. You really die of some kind of sepsis or staph infection, then turn into a zombie after your dead.

takes off professor hat, kicks the door, and leaves while brandishing devil horns

There are a lot of viruses out there that embed themselves in a host's cells/DNA and can lay dormant for years, or even decades, before becoming activated by the right conditions.

I've always assumed that everyone was infected by the virus, which is now laying dormant in their bodies until being activated by their death. The reason bites, and even just scratches, kill are because the "active" version of the virus is introduced and activates the dormant version of the virus already present in the victim's body. It also explains how someone who has just turned, and wouldn't have built up the kind of bacteria to kill someone, can still kill someone from a single bite.

I don't know if this is canon or not, but it makes sense to me. In the end, it's just an excuse to set up the rules/conditions of this world. How we get there isn't really all that important.

*EDIT: And that's why you read a thread all the way to the end. DEADinTHEhead beat me to it.

I think of it this way: everyone is infected, but until a person dies the virus cant invade the "blood/brain barrier" and reproduce because of the body's immune system, so the virus stays in check. But in the case of a bite, the virus has already crossed the barrier in the walker doing the biting, where it reproduced unchecked, and when the walker bites someone, massive amounts of virus are transfered into the victim's bloodstream, on top of what was already there. This sets the immune system into overdrive, hence the extreme fever a bite victim experiences. The massive immune system response to the virus kills the victim, and then the virus moves through the unprotected "blood/brain barrier" and reproduces, starting the cycle again.

Everyone has the virus inside them but it only activates once the person's dead. The bite actually does not contain the "Walker Virus" but the saliva of those walkers contains many deadly pathogens that humans can't fight against, thus killing them in a matter of hours. Then the "Walker Virus" activates and brings them back as mindless flesh-eating corpses.

The bite is just a sure-kill method. Well, that's how I see it at least.